"Wheeler is much smarter and will try to keep his efforts under the radar in implementing Trump's destructive agenda," Vice President for Political Affairs at the Environmental Defense Fund Jeremy Symons told POLITICO. "That should scare anyone who breathes."

Wheeler began his DC career at the EPA as a special assistant in the pollution prevention and toxics office, according to his EPA bio. He has now been in DC for more than 20 years, and followed up his EPA post by working for infamous climate change denier and Republican Oklahoma Senator James Inhofe, The New York Times reported. Inhofe once even threw a snowball on the Senate floor to assert that global warming wasn't happening, according to Vox.

Wheeler is one of several former Inhofe staffers, known as the "Inhofe mafia," who have risen to prominent environment or energy positions in the Trump administration or work with influential lobbying firms, according to The New York Times.

After leaving government work, Wheeler worked at a law firm that lobbied for the coal industry, NBC reported. His firm's biggest client was Murray Energy Corp., whose CEO, Robert E. Murray, donated $300,000 to Trump's inauguration fund and provided Trump with a wishlist of environmental policies he wanted changed to benefit coal plants, The New York Times reported.

Environmental groups are concerned about the legacy Wheeler brings with him as he prepares to lead the EPA.

"He fought against safeguards to limit mercury poisoning. He fought against protections to limit the amount of ozone in our skies. He fought against air pollution from neighboring states. He's a climate denier. So, sadly, he fits in well with EPA leadership," Sierra Club Executive Director Michael Brune told POLITICO.

Critics are also concerned that Wheeler's decades of experience, and reputation as a rule follower, will mean his deregulatory efforts will stand up to legal scrutiny more effectively than Pruitt's rushed attempts at rollbacks.

"The problem with the Pruitt approach is it's like a sugar high," Democratic lobbyist and former Energy Department staff member Jeff Navin told POLITICO. "It feels really, really good for a moment, but if you're not following rules and procedure, not laying down substance for the decision you're making, you're not going to last very long."

But that is not Wheeler's style. "He will be similar to Pruitt in terms of the agenda—he understands the Trump administration and will carry out the agenda," Matthew Dempsey, who worked for Inhofe alongside Pruitt, told The New York Times. "But he's been around Washington a long time. He knows how DC works and he does things by the book."

However, it is not known how long Wheeler will head the EPA before Trump nominates a permanent replacement for Pruitt. Trump might suggest Wheeler for the role, but The New York Times reported that Wheeler himself has said he does not want the job. He also wrote a Facebook post critical of Trump during the 2016 election, which might dissuade the president from selecting him.

Other possible permanent replacements for Pruitt include Donald Van der Vaart, a senior environmental official from North Carolina who Pruitt appointed to an EPA scientific advisory board, The New York Times reported.

An image of the trans-alaskan oil pipeline that carries oil from the northern part of Alaska all the way to valdez. This shot is right near the arctic national wildlife refuge. kyletperry / iStock / Getty Images Plus

The Trump administration has initialized the final steps to open up nearly 1.6 million acres of the protected Alaskan National Wildlife Refuge to allow oil and gas drilling.

A Florida man has been allowed to import a Tanzanian lion's skin, skull, claws and teeth, a first since the animal was listed as threatened under the Endangered Species Act, according to US Fish and Wildlife Service records uncovered by the Center for Biological Diversity through the Freedom of Information Act.

A fracked natural gas well in northwest Louisiana has been burning for two weeks after suffering a blowout. A state official said the fire will likely burn for the next month before the flames can be brought under control by drilling a relief well.